In the commercial growing and harvesting of forest products, trees are not simply planted and harvested at a pre-determined time in the future. Instead, many silviculture techniques may be applied to a forest stand during its growth cycle in order to achieve an optimal yield for a particular type of forest product. Such techniques can include selective thinning of desired trees, the removal of competing trees, brush or other vegetation, the application of fertilizer, etc.
One difficulty encountered in active management forestry is to know which stands are not growing as expected and therefore may need fertilization, thinning or the administration of other silvicultural techniques. The conventional method of forest management is to send foresters into a stand to physically survey the stand and recommend the application of one or more silviculture techniques if needed. While such an approach can work for relatively small forests, it can be cost prohibitive to physically inspect all the areas of large commercial forests that may extend over a wide large geographical area. In addition, even if physical inspection is possible, a survey crew generally doesn't know ahead of time what the condition of the stand will be prior to its inspection. Therefore, the crew often has to return to the site with the proper equipment in order to perform a recommended silviculture technique.